Air cooling system having expansion means



June 19, 1951 C. W. MORRIS AIR .CO OLING SYSTEM HAVING EXPANSION MEANSOriginal Filed July 20, 1945 lNVENTOR CHARLES W; MORRIS ATTORNEYPatented June 19, 1951 AIR. COOLING SYSTEM HAVING EXPANSION MEANSCharles W. Morris, West Los Angeles, Calif., assignor to The GarrettCorporation, Los Angeles, Calii'., a corporation oi California Originalapplication July 20, 1945, Serial No.

606,179. Divided and this application February 27, 1950, Serial No.146,437

15 Claims.

My invention relates in general to air conditioning equipment andrelates in particular to a simple device for reducing the temperature ofair which need not involve the use of a condensable refrigerant.

This application is a division of my co-pending application, Serial No.606,179, filed July 20, 1945, i'or Supercooler, now Patent No.2,518,246, granted Aug. 8, 1950.

It is an object of the invention to provide an air cooler which usesatmospheric air as the coolant or heat abstracting medium, whereby aflow of air, also drawn from the atmosphere, is cooled.

A further object of the invention is to provide a device in which theair to be cooled is compressed so as to raise its temperature above thatof the surrounding air, or atmospheric air from which the air to becooled is drawn, the compressed air being then passed through a cooler,which employs atmospheric air as a coolant, and then reexpanded to thepressure of the chamber in which it is to be used, or which is to beairconditioned, this reexpansion of the cooled, compressed airaccomplishing a reduction in its temperature to a value below thetemperature of the outer atmosphere and also recovering a usable portionof the power expended in the compression of the air. I

It is an Object of the invention to provide a simple device which byitself is an important and independently usable air-conditioning unit,but which may be used with other air-conditioning equipment where aclose control of temperature and humidity is required. An importantusefulness of the invention, due to its small size and weight, is inconnection with systems for pressurizing aircraft cabins, in whichsystems the compression of air results in a rise in its temperature sothat unless the compressed air is cooled before it is delivered into thecabin, the cabin interior will be heated to a temperature higher than iscomfortable for the occupants. The device shown herein may be connectedin series into a duct through which air under pressure is delivered to acabin or other space for the purpose of pressurization.

A further object of the invention is to provide an air cooler having arelatively light supporting structure which defines a central air space,there being air cooling means arranged on opposite sides of or aroundthis air space, and simple means for directing air to be cooled throughthe cooling means andalso for directing atmospheric air into the centralspace so that it will move in a generally radial direction through thecoolant passages of the cooling means.

A further object of the invention is to provide a device of thecharacter set forth in the preceding paragraph wherein the supportingstructure is provided with bearings for rotatably supporting a shaftwhich extends lengthwise through the central air space and has its rearend connected to the moving part of an air-operated engine through whichthe cooled compressed air is reexpanded, the power derived from suchreexpansion of the air being carried by the shaft to a power utilizingmeans disposed at the front end of the supporting structure.

A further object is to provide in a device of this character a meanswhereby the recovered power which is transmitted to the shaft isutilized, at least in part, in the compression of the air to be cooled.

It is one of the objects of my invention to provide a method andapparatus whereby there is established a path of flow for replenishmentair for the cabin and in which path there is located power absorbingparts which are driven by the flow of air in said path, the absorbing ofpower by said parts extracting heat from the replenishment air.

It is also an object of my invention to provide a method and apparatusof the character as pointed out in the preceding paragraph, in whichthere is a cooler means located in the path for the replenishment airlocated on the intake side of said means having the power absorbingparts.

A further object of the invention is to provide a simple air turbinearrangement whereby the cooled and compressed air is reexpanded so as tobe further cooled and power is recovered as a result of suchreexpansion.

Further objects and advantages of the invention will be brought out inthe following part of the specification.

Referring to the drawings which are for illustrative purposes only:

Figure 1 is a sectional view constituting a simplified, somewhatschematic, showing of a preferred embodiment of my invention;

Figure 2 is a sectional view taken as indicated by the line 2-2 oi Fig.1.

.In the drawings, I have shown in a somewhat schematic manner a form ofthe invention wherein many of the constructional characteristics of thedevice disclosed in said c'o-pending application, Serial No. 606,179 arerepeated. In this form of the invention the means -for compressing theair to be cooled is shown as a compressor 40 which delivers thecompressed air through a duct II to an annular manifold 42 communicatingwith the front endsof cooler tubes 43 which ex- 3 tend from a plate 44to a plate 45, these tubes 43 being arranged so as to form a cage arounda central air space 45. A cooling air inlet housing 41 is connected tothe front face of the plate 44 in a position to direct air, as indicatedby arrows 48, through the air inlet openings49 of the plate 45 to theair space 46, from which the air flows outwardly through the spacesbetween the tubes 43 as indicated by arrows 58.

A shaft is extended through the space 46 defined by the supportingstructure consisting of the end plates 44 and and the tubes 43. Thisshaft 5| has on its front end 52 a means 53 for recovering power fromthe air which issues from nozzles 54 at the rear ends of the tubes 43.The opposite end of the shaft 52 is connected to a means 55 forutilizing the power recovered from the compressed air after it haspassed through the cooling tubes 43. The power recovering means 53consists of a rotor having vanes 56 positioned so as to be impinged bythe jets of air which issue from the nozzle 54. As shown in Figure 2,the nozzles 54 are inclined in the direction of rotation desired for therotor 53, and these nozzles are formed in a simple manner by taperingthe rear ends of the tubes 43 which project through the plate 45 andthen bending these tapered ends to the desired angle, thereby providingthe diagonally directed nozzles 54. The

pow'er utilizing means 55, which places a load on the shaft 5| to resistfree rotation of the rotor 53, may consist of any power-drivenmechanism, such, for example, as an oil circulating pump.

A conoidal housing 51 is connected to the rear face of the end plate 45in a position to cover the rotor 53. The reduced outlet 58 of thehousing 57 projects into a housing 59 from which there extends an airoutlet connection 66 adapted to be connected to a duct or other spacewhich is to receive the cooled air. From the compressed air inlet duct4| an air bypass duct 6 I has therein a valve throat 62 controlled by aconical valve member 63 which is mounted on a slidably disposed shaft64. This shaft 64 extends into a housing 65 which is divided intoadjacent pressure chambers 66 and6'l by a diaphragm 68. The centralportion of the diaphragm 68 is connected to the shaft 64, and themovement of the diaphragm by differential pressure between the chambers66 and 61 is transmitted through the shaft 64 to the valve 63.Controlling air pressure is transmitted from a control unit, not shown,through air ducts 69 and ID. A lever H is pivotally mounted upon thehousing 65 and one of its ends is connected to the projecting end 12 ofthe shaft 64, thereby providing externally of the housing 65 a memberwhich has move ment in accordance with the movement of the valve 63, towhich the follow-up mechanism of the control unit may be connected.

The coolant air which is directed through the housing -4! may be derivedfrom any source of air pressure. In an aircraft it may be obtained froman air rammed duct. It will be understood that in the operation of thisdevice the proportions of air directed through the cooler and throughthe bypass 6| are varied in accordance with the deviation of thetemperature in the airconditioned space supplied by the device from theselected temperature. The control of the bypass valve 63 may be manual,or may be accomplished by use of automatic temperature-responsivecontrol mechanism not forming a part of this invention. In the inventionshown herein the work done by the air in driving the reexpansionturbines constitutes an absorption of energy which has been convertedfrom pressure energy to kinetic energy. Therefore this conversion ofenergy results in a cooling of the air in addition to the cooling effectresulting from the mere increase in volume of the air after it reachesthe tubes of the coolers.

I claim:

1. In an air cooler, the combination of a supporting structure definingan air space having an inlet at the front end thereof; a shaft memberextending through said structure from the front to the rear end thereof;bearing means carried by said structure supporting said shaft member forrotation; cooling means arranged along said air space, said coolingmeans having first passages extending from the front end of saidstructure to the rear end thereof and second passages in crossingrelation to said first passages, said second passages communicating withsaid air space; compressor means for compressing the air to be cooledand delivering the same into the front ends of said first passages; areexpansion turbine at the rear end of said structure for receiving thecooled compressed air from said first passages, the rotor of saidturbine being connected to the rear end of said shaft; power recoverymeans connected to said shaft so as to apply a load to said turbine; andmeans for bypassing a portion of the air from said compressor meansaround said cooling means.

2. In an air cooler, the combination of: a plurality of tubes arrangedin side-by-side relation so as to form a cage around a central space; awall closing one end of said space; means for delivering coolant airinto the other end of said space so that it will flow out through thespaces between said tubes; compressor means for delivering air to becooled into the front ends of said tubes; turbine means at the rear endsof said tubes to receive the air which has been cooled in passingthrough said tubes, said cooled air drivin said turbine means; and meansfor bypassing a portion of the air from said compressor means aroundsaid turbine means so that the bypassed portion of the air will not becooled.

3. In an air cooler, the combination of: a plurality of tubes arrangedin co-extending relation so as to surround a central space; a frontplate and a rear plate in spaced relation and having openings therein toreceive the ends of said tubes; means for delivering coolant air intosaid space so that it will fiow out through the spaces between saidtubes; means for delivering air to be cooled into the front ends of saidtubes; air nozzles at the rear ends of said tubes; and a rotatablysupported turbine rotor having vane means disposed so as to receive airfrom said nozzles whereby said turbine rotor will be driven and said airfrom said nozzles further cooled. I

4. In a system for cooling air to be delivered to a space in an aircrafthavin an air rammed duct and air compressin means for compressing saidair; a cooler having cooling passages for the compressed air and otherpassages for coolant air; inlet means for delivering air from said aircompressing means to said cooling passages of said cooler; workextracting means comprising an expansion engine receiving cooled airfrom said cooler; and means for directing coolant air from an air rammedduct of the aircraft through said other passages of said cooler. 5, In asystem for cooling air to be delivered to a space in an aircraft: aircompressing means for compressin the air; duct means defining a path offlow for the air from said air compressing means to said space; a coolerin said path of flow downstream from said air compressing means; workextracting means comprising a cooling turbine in said path of flowdownstream from said cooler; a bypass having its front end connected tosaid path of flow upstream from said work extracting means and its rearend connected to said path of flow downstream from said work extractingmeans; and control valve means adapted to control the proportions of theflows of air through said heat extractin means and said bypass.

6. In a system for cooling air to be delivered to a space in an aircrafthaving air compressing means for compressing the air and a source ofcoolant air: duct means defining a path of flow for the air from saidair compressing means to said space; a cooler downstream from said aircompressing means having passages for the compressed air in said path offiow, and having coolant air passages; means for directing air from saidsource of coolant air through said coolant air passages; work extractingmeans comprising a cooling turbine in said path of flow downstream fromsaid cooler; a bypass having its front end connected to said path'offlow upstream from said work extracting means and its rear end connectedto said path of fiow down stream from said work extractin means; andcontrol valve means adapted to control the proportions of the flows ofair through said heat extracting means and said bypass.

7. In a system for cooling air to be delivered toa space in an aircrafthaving air compressing means for compressing the air and a source ofcoolant air: duct means defining a path of flow for the air from saidair compressing means to said space; a cooler downstream from said aircompressing means having passages for the compressed air in said path offlow, and having coolant air passages; means for directing air from saidsource of coolant air through said coolant air passages; and workextracting means comprising a cooling turbine in said path of flowdownstream from said cooler.

' tracting means and adapted to be connected to the space to be cooled.

9. In a system for cooling air to be delivered to a space in anaircraft: air compressing means for compressing the air; a cooler havingcooling passages for the compressed air; inlet means for delivering airfrom said air compressing means to said cooling passages of said cooler;work extracting means comprising a cooling turbine receiving cooled airfrom said cooler; outlet means receiving cooled air from said workextracting means and adapted to be connected to the space to be cooled;a bypass connecting said inlet and said outlet means; 'and means havinga movable wall adapted to control proportionate flow of air through saidbypass.

10. In a system for cooling air to be delivered to a space in anaircraft: air compressing means for compressing the air; a cooler havingcooling passages for the compressed air; inlet means for delivering airfrom said air compressing means to said cooling passages of said cooler;work extracting means comprising an expansion engine receiving cooledair from said cooler; outlet means receiving cooled air from said workextracting means and adapted to be connected to the space to be cooled;a bypass connecting said inlet and said outlet means; valve meansadapted to con,- trol proportionate flow of air through said bypass; andtemperature controlled valve actuating means connected to said valvemeans.

11. In a system for cooling 'air to be delivered to a space in anaircraft: air compressing means for compressing the air; duct meansdefining a path of flow for the air from said air compressing means tosaid space; a cooler in said path of flow downstream from said aircompressing means; work extracting means comprising an expansion enginein said path of flow downstream from said cooler; and a bypass havingits front end connected to said path of flow upstream from said workextracting means and its rear end connected to said path of flowdownstream from said work extracting means.

12. In a device for cooling air to be delivered to a space in anaircraft, the combination of a cooler having passage means for the airand other passage means for a coolant; inlet means for conducting saidair under pressure to the inlet of said cooler; a turbine connected soas to receive and be driven by the air leaving said cooler; meanscoupled to said turbine to utilize power developed by said turbine; andan outlet member to receive said air which has passed through saidturbine, adapted for. delivery of said air to said space. v

13. In a. system for cooling air to be delivered to a space in anaircraft, the combination of:

' duct means defining a path for the flow of air to said space; a coolerin said path of flow for cooling said air; work extraction meanscomprising an expansion turbine in said path of flow on the downstreamside of said cooler; means coupled to said turbine to utilize powerdeveloped by said turbine; air compression means connected to said ductmeans on the upstream side of said cooler; and a bypass connected tosaid duct means whereby air may be bypassed around said cooler and saidturbine.

14. Mechanism for conditioning compressed air which is conducted from asource of compressed air to a cabin, comprising: cooler means havingfirst and second passage means in heat transfer relation to each other;means for directing a flow of compressed air from said source throughsaid first passage means to said cabin; means for directing a fiow ofcoolant through said second passage means for cooling said compressedair flowing through said first passage means; a cooling turbine in thepath of flow of at least a part of the compressed air for cooling thesame; and means for bypassing air from said first passage means aroundsaid turbine to said cabin.

l5. Mechanism for conditioning compressed air which is conducted from asource of compressed air to a cabin, comprising: cooler means havingfirst and second passage means in heat transfer relation to each other;means for directing a flow of compressed air from said source throughsaid first passage means to said cabin; means for directing a fiow ofcoolant through said second passage means for cooling said compressedair flowing through said first passage means; a

cooling turbine in the path of flow of at least a part of the compressedair for cooling the same; and means responsive to the temperature of airwhich has been cooled by said turbine for bypassing air from said firstpassage means 5 around said turbine to said cabin.

. CHARLES W. MORRIS.

REFERENCES CITED The following references are of record in the 10 tileor this patent:

' Number 8 UNITED STATES PATENTS Name Date Kleinhans Dec. 25, 1945Williams Dec. 3, 1946 Meyer June 14, 1949 Wood Aug. 23, 1949

